java - how many classes per package? methods per class? lines per method?

Question

I have to give a general note to some huge Java project for which I have but little visibility and I was wondering if there were any guidelines for determining:

• what number of classes per package can be considered right, to low, or to high (this project has 3.89 classes per package, which seems a bit too small for me),
• number of methods per class? (this project has 6.54 methods per class...
• number of lines per method? (this project has about 7 lines per method (seems pretty good to me, maybe a bit low))

I should note that this question is only dealing with volumetry. I have a bunch of reports from quality tools (checkstyle, jdepend, cpd, pmd, ncss) that give me more vision about code redundancy, classes usage, bugs, etc.

Answer 1

Steve McConnell in his book Code Complete recommends about 7 methods per class and no more lines in a method then can be viewed in a single screen without scrolling.

I'm not sure about classes per package.

I would highly recommend reading Code Complete for more information on such topics.